Scientists spot human immunity switch

London: Scientists have for the first time identified the molecular mechanism that alert our immune system to go on the defensive against germs and other invaders in our bloodstream — a breakthrough that could lead to treatments for a range of conditions from auto-immune diseases to cancer.

The inner workings of T-cells, the front-line troops were observed with the help of the only microscope of its kind in Australia. The discovery overturns prevailing understanding, identifying the exact molecular ``switch`` that spurs T-cells into action.

The technology is a major breakthrough for science, said Associate Professor Katharina Gaus from University of New South Wales’ Centre for Vascular Research. “Currently there are only half a dozen of the ``super`` microscopes in use around the world.

"Previously you could see T-cells under a microscope but you couldn``t see what their individual molecules were doing," Dr Gaus said.

Using the new microscope the scientists were able to image molecules as small as 10 nanometres. Dr Gaus said that what the team found overturns the existing understanding of T-cell activation.

Dr Gaus said the discovery explained how the immune response could occur so quickly.